High-temperature corrosion of three austenitic boiler steels, B-407, X8CrNiNb1613 and X8CrNiMoNb1616, was tested experimentally in laboratory in conditions of superheater of oil shale boiler in the presence of chlorine-containing external deposits. The empirical kinetic equations for calculation of corrosion depth depending on operational time and temperature were established. The best corrosion resistance was shown by steel X8CrNiMoNb1616.